STM32G474VET6 DFU USB

[Spam4tea]

Hello All

I am having problems getting the STM32G474VET6 to enter bootloader mode DFU-USB.

The STM32G474VET6 USB works perfectly in application mode (VCP) - no trouble there.

But holding BOOT0 high (with default option bytes) and resetting it will not enter bootloader mode - I have looked over AN2606 and AND3156 and can’t see a reason why it would not run. I did have an older prototype with a STM32G474RET6 which worked just fine over USB. 

I have also tried to get the bootloader to workover UART1 but this also fails - can anyone see a reason bootloader would fail to run? (UART1 connected to the debug header and also works fine in the application)

 

[Spam4tea]

is 

 a similar issue? 

[Spam4tea]

Now where would that be???

[TDK]

Look at the option bytes in STM32CubeProgrammer and ensure they are consistent with what is required in AN2606. Show a screenshot to confirm.

If another bootloader peripheral is active, it will jump to that one. Ensure all other supported bootloader pins (e.g. USART_RX pins) are quiet while chips restarts.